Accuracy of holmium-166 SPECT/CT quantification over a large range of activities.

Background: Quantitative imaging is a crucial step for dosimetry in radionuclide therapies. Traditionally, SPECT/CT imaging is quantified based on scanner-specific conversion factors or self-calibration, but recently absolute quantification methods have been introduced in commercial SPECT reconstruction software (Broad Quantification, Siemens Healthineers). In this phantom study we investigate the accuracy of three quantification methods for holmium-166 SPECT/CT imaging, and provide recommendations for clinical dosimetry.

Gallium-68 labelled RGD PET/CT imaging of endothelial activation in COVID-19 patients.

In coronavirus disease 2019 (COVID-19), endothelial cells play a central role and an inadequate response is associated with vascular complications. PET imaging with gallium-68 labelled RGD-peptide (Ga-RGD) targets αβ integrin expression which allows quantification of endothelial activation. In this single-center, prospective observational study, we included ten hospitalized patients with COVID-19 between October 2020 and January 2021.

New Radiolabeled Exendin Analogues Show Reduced Renal Retention.

PET imaging of the glucagon-like peptide-1 receptor (GLP-1R) using radiolabeled exendin is a promising imaging method to detect insulinomas. However, high renal accumulation of radiolabeled exendin could hamper the detection of small insulinomas in proximity to the kidneys and limit its use as a radiotherapeutic agent. Here, we report two new exendin analogues for GLP-1R imaging and therapy, designed to reduce renal retention by incorporating a cleavable methionine-isoleucine (Met-Ile) linker.

Impact of tyrosine kinase inhibitors on glucose control and insulin regulation in patients with chronic myeloid leukemia.

Treatment with tyrosine kinase inhibitors (TKIs), especially nilotinib, often results in hyperglycemia, which may further increase cardiovascular disease risk in patients with chronic myeloid leukemia (CML). The mechanism underlying the TKI-induced glucose dysregulation is not clear. TKIs are suggested to affect insulin secretion but also insulin sensitivity of peripheral tissue has been proposed to play a role in the pathogenesis of TKI-induced hyperglycemia.

Improving MRI-based dosimetry for holmium-166 transarterial radioembolization using a nonrigid image registration for voxelwise calculation.

Background: Transarterial radioembolization (TARE) is a treatment modality for liver tumors during which radioactive microspheres are injected into the hepatic arterial system. These microspheres distribute throughout the liver as a result of the blood flow until they are trapped in the arterioles because of their size. Holmium-166 ( Ho)-loaded microspheres used for TARE can be visualized and quantified with MRI, as holmium is a paramagnetic metal and locally increases the transverse relaxation rate .

Contralateral Regional Recurrence in Lateralized or Paramedian Early-Stage Oral Cancer Undergoing Sentinel Lymph Node Biopsy-Comparison to a Historic Elective Neck Dissection Cohort.

Nowadays, two strategies are available for the management of the clinically negative neck in early-stage (cT1-2N0) oral squamous cell carcinoma (OSCC): elective neck dissection (END) and sentinel lymph node biopsy (SLNB). SLNB stages both the ipsilateral and the contralateral neck in early-stage OSCC patients, whereas the contralateral neck is generally not addressed by END in early-stage OSCC not involving the midline. This study compares both incidence and hazard of contralateral regional recurrences (CRR) in those patients who underwent END or SLNB.

Phase I study to assess safety, biodistribution and radiation dosimetry for Zr-girentuximab in patients with renal cell carcinoma.

Purpose: In this phase I study, we evaluated the safety, biodistribution and dosimetry of [Zr]Zr-DFO-girentuximab (Zr-girentuximab) PET/CT imaging in patients with suspicion of clear cell renal cell carcinoma (ccRCC).

Methods: Ten eligible patients received an intravenous administration of 37 MBq (± 10%) of Zr-girentuximab at mass doses of 5 mg or 10 mg. Safety was evaluated according to the NCI CTCAE (version 4.

Elective Neck Dissection or Sentinel Lymph Node Biopsy in Early Stage Oral Cavity Cancer Patients: The Dutch Experience.

Background: Sentinel lymph node biopsy (SLNB) has been introduced as a diagnostic staging modality for detection of occult metastases in patients with early stage oral cancer. Comparisons regarding accuracy to the routinely used elective neck dissection (END) are lacking in literature.

Methods: A retrospective, multicenter cohort study included 390 patients staged by END and 488 by SLNB.

A Clinical Feasibility Study to Image Angiogenesis in Patients with Arteriovenous Malformations Using Ga-RGD PET/CT.

Arteriovenous malformations (AVMs) have an inherent capacity to form new blood vessels, resulting in excessive lesion growth, and this process is further triggered by the release of angiogenic factors. Ga-labeled arginine-glycine-aspartate tripeptide sequence (RGD) PET/CT imaging may provide insight into the angiogenic status and treatment response of AVMs. This clinical feasibility study was performed to demonstrate that Ga-RGD PET/CT imaging can be used to quantitatively assess angiogenesis in peripheral AVMs.

Symmetry and spatial distribution of muscle glucose uptake in the lower limbs during walking measured using FDG-PET.

Purpose: This study aimed to elucidate whether muscle activity (in terms of glucose uptake) between the legs can be considered symmetrical during walking. Furthermore, we aimed to determine whether the [18F]-fluorodeoxyglucose was distributed heterogeneously throughout each muscle, and if so, whether areas of high uptake would be clustered.

Methods: Ten healthy participants walked on a treadmill at self-selected comfortable walking speed for a total of 90 minutes, 60 minutes before and 30 minutes after intravenous injection of 50 MBq [18F]-fluorodeoxyglucose.

In Vivo Characterization of 4 Ga-Labeled Multimeric RGD Peptides to Image αβ Integrin Expression in 2 Human Tumor Xenograft Mouse Models.

αβ integrins play an important role in angiogenesis and cell migration in cancer and are highly expressed on the activated endothelial cells of newly formed blood vessels. Here, we compare the targeting characteristics of 4 Ga-labeled multimeric cyclic arginine-glycine-aspartate (RGD)-based tracers in an αβ integrin-expressing tumor model and a tumor model in which αβ integrin is expressed solely on the neovasculature. Female BALB/c nude mice were subcutaneously injected with SK-RC-52 (αβ integrin-positive) or FaDu (αβ integrin-negative) tumor cells.